Solve Vector Problems: Displacements & Components | Find r, Angle, & Components

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The discussion revolves around solving vector problems involving three displacements represented in terms of i, j, and k components. The calculations for the resultant vector r, derived from the equation r = d1 - d2 + d3, yield specific values for the i, j, and k components. The angle between r and the positive z-axis is calculated using the inverse cosine function, resulting in an angle of approximately 104.3 degrees. Additionally, the component of d1 along the direction of d2 is computed, although there is some uncertainty expressed regarding the accuracy of this calculation. The discussion also addresses finding the component of d1 that is perpendicular to d2, emphasizing the importance of understanding vector projections and magnitudes.
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Here are three displacements, each in meters:
d1 = 9i + 5j - 3k
d2 = -1i + 1j + 3k
d3 = 4i + 3j + 2k What is r = d1 - d2 + d3 ((a), (b) and (c) for i, j and k components respectively)?
(d) What is the angle between r and the positive z axis?
(e) What is the component of d1 along the direction of d2?
(f) What is the component of d1 that is perpendicular to the direction of d2 and in the plane of d1 and d2?a) 14i
b) 7j
c) -4k
d) cos-1(-4/sqrt14²+7²+4²) = 104.3
e) (-9+5-9)/(sqrt(1²+²+3²) = -3.92i am having difficulty with e and f i tried e not sure if right but don't understand f

thanks in advance
 
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f) [(magnitude of d1)^2 - (the component of d1 along the direction of d2)^2]^1/2
 
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